Struct Semaphore 

pub struct Semaphore { /* private fields */ }

A counting semaphore without priority inheritance or task ownership.

up and try_down are IRQ-safe. Blocking acquisition is task-only and grants queued waiters in FIFO order without allowing a new caller to steal a published grant.

Implementations

impl Semaphore

pub const fn new(permits: usize) -> Semaphore

Creates a semaphore with permits initially available grants.

pub fn try_down(&self) -> bool

Consumes one available permit without blocking, including in IRQ context.

pub fn up(&self) -> Result<(), SemaphoreError>

Releases a permit or directly grants the oldest queued waiter.

pub fn down(&self) -> Result<(), SemaphoreError>

Waits without interruption until one permit is granted.

pub fn down_interruptible( &self, interrupted: impl FnMut() -> bool, ) -> Result<(), SemaphoreError>

Waits until a permit is granted or an ordinary wake observes interruption. The interruption publisher must also wake this task.

pub fn down_until( &self, deadline: MonotonicDeadline, ) -> Result<(), SemaphoreError>

Waits for a permit until an absolute monotonic deadline.